Talk to your local extension agent about stocking rates in your area. You are probably in the 6-8 acre range for pairs, and 5-6 acres for calves. Depending on the terrain, your acres might not be suited for a haying operation. I.e. rocks, steep slopes, etc. You also need to look at the fences. Assuming since someone else has been renting it out, they must be in decent shape. I do think you could make more money running your own cows/calves vs. renting it out, but you obviously take all the risk.
Venturing into the cow/calf business with little to no experience could be a bad idea, and you could lose your $50k pretty fast. I wouldn't start out buying really expensive registered animals if you do go the cow/calf route. Buy some good 3-5 year old cows from a reputable producer. They will have many years of life left in them, and should raise you some good cows. In Kansas, blacks and black baldies sell real well. I would recommend buying some british based cows, and use a continental bull on them. I would shoot for some black white faced cows, (Angus/hereford cross) and put either a Gelbvieh or Simmental bull on them. That will maximize your heterosis and give you marketable calves.
Backgrounding calves can be a profitable venture to, and you don't have to tend to cows in the winter time and deal with calving them out, etc. This might be your best option to get your feet wet, and then you can move to the cow/calf operation if you like.
Whatever you do, don't do too much too fast, or you could lose your tail. I am pretty familiar with your area, send me a PM if you have any questions you would like to ask.